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<H1 class="no-header">curs_pad 3x</H1>
<PRE>
<STRONG><A HREF="curs_pad.3x.html">curs_pad(3x)</A></STRONG>                                                      <STRONG><A HREF="curs_pad.3x.html">curs_pad(3x)</A></STRONG>




</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>newpad</STRONG>, <STRONG>subpad</STRONG>, <STRONG>prefresh</STRONG>, <STRONG>pnoutrefresh</STRONG>, <STRONG>pechochar</STRONG>, <STRONG>pecho_wchar</STRONG> - create
       and display <STRONG>curses</STRONG> pads


</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
       <STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>

       <STRONG>WINDOW</STRONG> <STRONG>*newpad(int</STRONG> <EM>nlines</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>ncols</EM><STRONG>);</STRONG>
       <STRONG>WINDOW</STRONG> <STRONG>*subpad(WINDOW</STRONG> <STRONG>*</STRONG><EM>orig</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>nlines</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>ncols</EM><STRONG>,</STRONG>
             <STRONG>int</STRONG> <EM>begin</EM><STRONG>_</STRONG><EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>begin</EM><STRONG>_</STRONG><EM>x</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>prefresh(WINDOW</STRONG> <STRONG>*</STRONG><EM>pad</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>pminrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>pmincol</EM><STRONG>,</STRONG>
             <STRONG>int</STRONG> <EM>sminrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smincol</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smaxrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smaxcol</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>pnoutrefresh(WINDOW</STRONG> <STRONG>*</STRONG><EM>pad</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>pminrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>pmincol</EM><STRONG>,</STRONG>
             <STRONG>int</STRONG> <EM>sminrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smincol</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smaxrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smaxcol</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>pechochar(WINDOW</STRONG> <STRONG>*</STRONG><EM>pad</EM><STRONG>,</STRONG> <STRONG>chtype</STRONG> <EM>ch</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>pecho_wchar(WINDOW</STRONG> <STRONG>*</STRONG><EM>pad</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>cchar_t</STRONG> <STRONG>*</STRONG><EM>wch</EM><STRONG>);</STRONG>


</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>

</PRE><H3><a name="h3-newpad">newpad</a></H3><PRE>
       The <STRONG>newpad</STRONG> routine creates and returns a pointer  to  a  new  pad  data
       structure  with  the given number of lines, <EM>nlines</EM>, and columns, <EM>ncols</EM>.
       A pad is like a window, except that it is not restricted by the  screen
       size,  and  is not necessarily associated with a particular part of the
       screen.  Pads can be used when a large window is  needed,  and  only  a
       part  of  the  window will be on the screen at one time.  Automatic re-
       freshes of pads (e.g., from scrolling or echoing of input) do  not  oc-
       cur.

       It  is  not  legal to call <STRONG>wrefresh</STRONG> with a <EM>pad</EM> as an argument; the rou-
       tines <STRONG>prefresh</STRONG> or <STRONG>pnoutrefresh</STRONG> should be  called  instead.   Note  that
       these routines require additional parameters to specify the part of the
       pad to be displayed and the location on the screen to be used  for  the
       display.


</PRE><H3><a name="h3-subpad">subpad</a></H3><PRE>
       The  <STRONG>subpad</STRONG> routine creates and returns a pointer to a subwindow within
       a pad with the given number of lines, <EM>nlines</EM>, and columns, <EM>ncols</EM>.   Un-
       like  <STRONG>subwin</STRONG>,  which uses screen coordinates, the window is at position
       (<EM>begin</EM>_<EM>x</EM><STRONG>,</STRONG> <EM>begin</EM>_<EM>y</EM>) on the pad.  The window is made in the middle of the
       window  <EM>orig</EM>,  so  that changes made to one window affect both windows.
       During the use of this routine, it will  often  be  necessary  to  call
       <STRONG>touchwin</STRONG> or <STRONG>touchline</STRONG> on <EM>orig</EM> before calling <STRONG>prefresh</STRONG>.


</PRE><H3><a name="h3-prefresh_-pnoutrefresh">prefresh, pnoutrefresh</a></H3><PRE>
       The  <STRONG>prefresh</STRONG>  and  <STRONG>pnoutrefresh</STRONG> routines are analogous to <STRONG>wrefresh</STRONG> and
       <STRONG>wnoutrefresh</STRONG> except that they relate to pads instead of  windows.   The
       additional  parameters  are needed to indicate what part of the pad and
       screen are involved.

       <STRONG>o</STRONG>   The <EM>pminrow</EM> and <EM>pmincol</EM> parameters specify the upper left-hand cor-
           ner of the rectangle to be displayed in the pad.

       <STRONG>o</STRONG>   The  <EM>sminrow</EM>,  <EM>smincol</EM>, <EM>smaxrow</EM>, and <EM>smaxcol</EM> parameters specify the
           edges of the rectangle to be displayed on the screen.

       The lower right-hand corner of the rectangle to be displayed in the pad
       is calculated from the screen coordinates, since the rectangles must be
       the same size.  Both rectangles must be entirely contained within their
       respective  structures.   Negative values of <EM>pminrow</EM>, <EM>pmincol</EM>, <EM>sminrow</EM>,
       or <EM>smincol</EM> are treated as if they were zero.


</PRE><H3><a name="h3-pechochar">pechochar</a></H3><PRE>
       The <STRONG>pechochar</STRONG> routine is functionally equivalent to  a  call  to  <STRONG>addch</STRONG>
       followed  by a call to <STRONG><A HREF="curs_refresh.3x.html">refresh(3x)</A></STRONG>, a call to <STRONG>waddch</STRONG> followed by a call
       to <STRONG>wrefresh</STRONG>, or a call to <STRONG>waddch</STRONG> followed by a call to  <STRONG>prefresh</STRONG>.   The
       knowledge  that  only  a single character is being output is taken into
       consideration and, for non-control characters, a  considerable  perfor-
       mance  gain  might  be  seen  by  using these routines instead of their
       equivalents.  In the case of <STRONG>pechochar</STRONG>, the last location of the pad on
       the screen is reused for the arguments to <STRONG>prefresh</STRONG>.


</PRE><H3><a name="h3-pecho_wchar">pecho_wchar</a></H3><PRE>
       The  <STRONG>pecho_wchar</STRONG>  function  is the analogous wide-character form of <STRONG>pe-</STRONG>
       <STRONG>chochar</STRONG>.  It outputs one character to a pad and  immediately  refreshes
       the pad.  It does this by a call to <STRONG>wadd_wch</STRONG> followed by a call to <STRONG>pre-</STRONG>
       <STRONG>fresh</STRONG>.


</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
       Routines that return an integer return <STRONG>ERR</STRONG> upon failure  and  <STRONG>OK</STRONG>  (SVr4
       only  specifies "an integer value other than <STRONG>ERR</STRONG>") upon successful com-
       pletion.

       Routines that return pointers return <STRONG>NULL</STRONG> on error, and  set  <STRONG>errno</STRONG>  to
       <STRONG>ENOMEM</STRONG>.

       X/Open does not define any error conditions.  In this implementation

          <STRONG>prefresh</STRONG> and <STRONG>pnoutrefresh</STRONG>
               return an error if the window pointer is null, or if the window
               is not really a pad or if the  area  to  refresh  extends  off-
               screen or if the minimum coordinates are greater than the maxi-
               mum.

          <STRONG>pechochar</STRONG>
               returns an error if the window is not really a pad, and the as-
               sociated call to <STRONG>wechochar</STRONG> returns an error.

          <STRONG>pecho_wchar</STRONG>
               returns an error if the window is not really a pad, and the as-
               sociated call to <STRONG>wecho_wchar</STRONG> returns an error.


</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       Note that <STRONG>pechochar</STRONG> may be a macro.


</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       BSD curses has no <EM>pad</EM> feature.

       SVr2 curses (1986) provided the <STRONG>newpad</STRONG> and related functions, document-
       ing  them  in  a single line each.  SVr3 (1987) provided more extensive
       documentation.

       The documentation does not explain the term <EM>pad</EM>.  However,  the  Apollo
       <EM>Aegis</EM> workstation operating system supported a graphical <EM>pad</EM> feature:

       <STRONG>o</STRONG>   These  graphical pads could be much larger than the computer's dis-
           play.

       <STRONG>o</STRONG>   The read-only output from a command could be scrolled back  to  in-
           spect, and select text from the pad.

       The two uses may be related.

       The  XSI  Curses  standard,  Issue 4 describes these functions, without
       significant change from the SVr3 documentation.  It describes no  error
       conditions.   The  behavior of <STRONG>subpad</STRONG> if the parent window is not a pad
       is undocumented, and is not checked by the vendor Unix implementations:

       <STRONG>o</STRONG>   SVr4 curses sets a flag in the <STRONG>WINDOW</STRONG>  structure  in  <STRONG>newpad</STRONG>  which
           tells if the window is a <EM>pad</EM>.

           However,  it  uses this information only in <STRONG>waddch</STRONG> (to decide if it
           should call <STRONG>wrefresh</STRONG>) and <STRONG>wscrl</STRONG> (to avoid  scrolling  a  pad),  and
           does  not  check  in  <STRONG>wrefresh</STRONG>  to ensure that the pad is refreshed
           properly.

       <STRONG>o</STRONG>   Solaris X/Open Curses checks if a window is a pad in  <STRONG>wnoutrefresh</STRONG>,
           returning <STRONG>ERR</STRONG> in that case.

           However,  it only sets the flag for subwindows if the parent window
           is a pad.  Its <STRONG>newpad</STRONG> function does not set this information.  Con-
           sequently, the check will never fail.

           It  makes no comparable check in <STRONG>pnoutrefresh</STRONG>, though interestingly
           enough, a comment in the source code states  that  the  lack  of  a
           check was an MKS extension.

       <STRONG>o</STRONG>   NetBSD  7 curses sets a flag in the <STRONG>WINDOW</STRONG> structure for <STRONG>newpad</STRONG> and
           <STRONG>subpad</STRONG>, using this to help with the  distinction  between  <STRONG>wnoutre-</STRONG>
           <STRONG>fresh</STRONG> and <STRONG>pnoutrefresh</STRONG>.

           It  does  not  check for the case where a subwindow is created in a
           pad using <STRONG>subwin</STRONG> or <STRONG>derwin</STRONG>.

           The <STRONG>dupwin</STRONG> function returns a regular  window  when  duplicating  a
           pad.   Likewise,  <STRONG>getwin</STRONG> always returns a window, even if the saved
           data was from a pad.

       This implementation

       <STRONG>o</STRONG>   sets a flag in the <STRONG>WINDOW</STRONG> structure for <STRONG>newpad</STRONG> and <STRONG>subpad</STRONG>,

       <STRONG>o</STRONG>   allows a <STRONG>subwin</STRONG> or <STRONG>derwin</STRONG> call to succeed having a  pad  parent  by
           forcing the subwindow to be a pad,

       <STRONG>o</STRONG>   checks  in  both  <STRONG>wnoutrefresh</STRONG> and <STRONG>pnoutrefresh</STRONG> to ensure that pads
           and windows are handled distinctly, and

       <STRONG>o</STRONG>   ensures that <STRONG>dupwin</STRONG> and <STRONG>getwin</STRONG> treat pads  versus  windows  consis-
           tently.


</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>, <STRONG><A HREF="curs_touch.3x.html">curs_touch(3x)</A></STRONG>, <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG>.



                                                                  <STRONG><A HREF="curs_pad.3x.html">curs_pad(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
<li><a href="#h3-newpad">newpad</a></li>
<li><a href="#h3-subpad">subpad</a></li>
<li><a href="#h3-prefresh_-pnoutrefresh">prefresh, pnoutrefresh</a></li>
<li><a href="#h3-pechochar">pechochar</a></li>
<li><a href="#h3-pecho_wchar">pecho_wchar</a></li>
</ul>
</li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
</ul>
</div>
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